PIP: Guidelines are provided for women who use minipills. Minipills are low dose, progestin only oral contraceptives (OC), which are frequently prescribed for women who 1) experience estrogen related side effects if they take combined OCs; 2) are 35 years of age or older; 3) are 30 years of age or aver and smoke; 4) have a history of headaches, hypertension, or varicose veins; 5) desire immediate postpartum protection; or 6) are lactating. Minipills prevent pregnancy by inhibiting ovulation and implantation and by making the cervical mucus more impervious to sperm penetration. Minipills can be effective if they are used properly. Women who take minipills should be advised to carefully read and follow the instructions provided in the OC packet, initiate pill taking on the 1st day of menstrual bleeding, and take 1 pill every day without and breaks. A backup method should be used during the 1st month and subsequently, during each midcycle phase. If a woman misses 1 pill, she should immediately, upon remembering, take a pill, take her next day's pill at regular time, and use a backup method until menstruation reoccurs. If a woman misses 2 pills, she should immediately, upon remembering, take 2 pills, take 2 pills the following day, and use a backup method until menstruation begins. Women should be advised that many minipill users experience irregular menstural cycles, including amenorrhea and spotting between periods. If menstruation is delayed for 45 days, a pregnancy test is advisable. Women should be advised to immediately seek medical attention if they experience severe chest pain, shortness breath, severe headaches, vision problems, or severe leg pain. Minipill users should let their clinicians know if they experience and changes in mood or sexual drive. These problems can frequently be avoided by switching to another brand of minipills.